HTG Molecular Diagnostics (HTGMQ) 10-K 2020 FY Annual report

Exhibit 4.2

HTG INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE LOGO HTG Molecular Diagnostics, Inc. COMMON STOCK CUSIP 40434H 20 3 SEE REVERSE FOR CERTAIN DEFINITIONS THIS CERTIFIES THAT specimen is the owner of FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK, PAR VALUE $0.001 PER SHARE, OF HTG Molecular Diagnostics, Inc. transferable on the books of the Corporation by the holder hereof in person or by duly authorized Attorney, upon surrender of this Certificate, properly endorsed. This Certificate is not valid until countersigned and registered by the Transfer Agent and Registrar. WITNESS the facsimile seal of the Corporation and the facsimile signatures of its duly authorized officers. Dated PRESIDENT SEAL SECRETARY AUTHORIZED SIGNATURE AND REGISTRAR TRANSFER AGENT Brooklyn, NY AMERICAN STOCK TRANSFER & TRUST COMPANY, LLC COUNTERSIGNED AND REGISTERED

The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations: TEN COM as tenants in common TEN ENT as tenants by the entireties JT TEN as joint tenants with right of survivorship and not as tenants in common UNIF GIFT MIN ACT Custodian (Cust) (Minor) under Uniform Gifts to Minors Act (State) Additional abbreviations may also be used though not in the above list. FOR VALUE RECEIVED hereby sell, assign and transfer unto PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE) Shares of the common stock represented by the within Certificate, and do hereby irrevocably constitute and appoint Attorney to transfer the said stock on the books of the within named Corporation with full power of substitution in the premises. Dated NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER Signature(s) Guaranteed: THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE 17Ad-15.